Brave new world of concrete

The Darwin Centre Phase II extension to the Natural History Museum in London, designed by C. F. Møller Architects, has been announced as Overall Winner of the 2009 Concrete Society Awards for Excellence in Concrete.

It is the building's iconic cocoon structure, formed from sprayed in-situ concrete, which convinced the judging panel. A high degree of innovation and co-operation in the design and construction process was necessary to achieve the extremely demanding outcome.

"The use of sprayed concrete was the obvious right choice for this project," states partner and architect Anna Maria Indrio. "The shell had to express mass and weight, in an enormous form that houses the collections, and concrete was the best material to achieve this. The cocoon is penetrated by a sequence of ramps, and the curved concrete shell remains visible everywhere. The magic atmosphere of the cocoon's interior is linked to the coarse expression of the material, and the result is perhaps the most spectacular shape we have created in concrete so far."

The brief for the building had three key objectives: to provide a home for 20 million plant and insect specimens, to provide a working area for the research scientists and to enable the public to interact with the scientists and the collections. This has been achieved by providing visitors with an opportunity to go on self-guided tours in and around the cocoon, which gives glimpses of the research facility and the extent of the collections.

One judge commented: "In the future, it is probable that this structure will become a benchmark for co-operation between all parties to the project and the production of extreme shapes in concrete. To adopt the shape of an egg to house such specimens was in itself imaginative. The challenges that it produced have been met to provide a highly impressive structure.”